• Preheat the oven to 175C (350C), Gas mark 4. Line the tin with non-stick baking parchment.

To make the caramelised pears, mix the pears with the lemon juice.  In a large frying pan, melt the butter and sprinkle with half the caster sugar. Put the pear quarters into the pan.  Cook for about 5 minutes until brown on one side.  Turn and cook for a further 5 minutes until the other side is brown.  With a slotted spoon, carefully remove the pear quarters and set aside to cool slightly.

• Add the bourbon and the rest of the caster sugar to the pan and cook and stir frequently for about 5 minutes until the mixture becomes syrupy.  Pour this syrup into the baking tin and tip the tin to spread evenly over the bottom of the tin.
• Start to arrange the pears from one corner so that they cover the bottom of the tin and are facing the same direction. Set aside.

To make the cake, sift together the flour, spices and salt in a bowl.

• Using a freestanding electric mixer with paddle attachment or hand-held electric whisk, cream the butter and sugar together for around 5 minutes on a medium-high speed until light and fluffy.  Add the eggs one at a time on a lower speed, scraping down the sides of the bowl after each addition.  Only beat until just Incorporated.  Add the molasses and beat for a few moments longer to mix.
• In a small bowl, add the boiling water to the bicarbonate of soda and set aside.  Add half the flour mixture to the creamed mixture on low speed.  then add the water and bicarbonate of soda and the rest of the flour mixture and mix until well Incorporated  It will look like the mixture has split, but that is correct.
• Scrape the mixture into the tin on top of the arranged pears and bake for 25 minutes.  Reduce the oven temperature to 165C (325F) Gas mark 3 and bake for 10-15 minutes longer.  
• The top should bounce bake when lightly touched.  Cool in the tin for 1 hour, then run a knife around the edges of the cake. Place a tray over the top of the tin and carefully(but quickly) turn upside down.